Permanent-mold construction



Wm 24, H. 8. LEE ET AL.

PERMANENT MOLD CONSTRUCTI ON Filed Feb. 2l, 1925 2 Sheets-Shwkl v klVVNTORS dry 66 y 1 #4020555? Wee BY 7 66? M'Zza rd A TTORNE Y.

Patented Nov. 24, 1%25.

\ UNITED HARRY S. LEE, All [0S E. CHAFFEE, AND FRED MILLARD, OFIPL'YEOUTH, MICHIGAN; ASSIGNORS OF THEIR ENTIRE BIG-HT TO THE 1 SAIDGHAFFEE AND SAID MILLAED 8AM) LEE.

ATENT? OFFICE.

PERMANENT-MOLD CONSTRUCTION.

To all whom it ma concern:

Be it known that we, HARRY S. LEE, Amos E. CHAFFEE, and Fnnn MILLARD,citizens of the United States, residing at Plymouth, in the county of.Wayne and State of Michigan, have invented certain new and usefulImprovements in Permanent-M0ld Construction, of which the following is aspecification.

This invention relates to mold construction, and more particularlypertains to molds provided with means whereby the meeting faces of themolds are automatically adjusted so that the same will remain perfectlyparallel, and therefore always meet.

With all molds, and especially so with molds that have a greaterrelative length than width, it is the tendency of them to how whenheated. These molds are subjected to very high temperatures, as themetal which is poured therein has a temperature of approximately 1700 to2000 degrees Fahrenheit. This causes the face of the mold to becomeextremely hot while the rear of the mold has a less temperature. Thiscauses the mold .to expand and when the mold is rigidly secured to thecarrier or support this expansion will cause the mold to bow out. Toovercome this tendency it is customary to only secure the mold to thesupport at one point thus allowing for expansion, in all directionsparallel to the face.

of the mold. However, it is found that the face of the mold expands at agreater rate than the rear of the mold which is more remote from thecasting, due to the tact of the difierence in temperature. Thisdifi'erence in expansion tends to bow out the mold or warp the same andit is found that the faces of the molds are not parallel, and preventsthe mold from forming a perfect joint.

Our invention pertains to means for controlling this warping or bowingaction in such a manner as to counteract the tendency of the mold to bowdue to the difl'erence in the rate of expansion between the face of themold and the rear portion of the mold.

In the drawin s:

Fig. l is an e evational view ofthe face of a mold which has aconsiderable length as compared with the width.

Fig. 2 is a vertical section on the lin 2-2 of Fig. l.

Fig. 3 is an enlarged detail of one end of the mold showing the dieexpanded.

.Fig. 4 is an enlarged modified detail of one end of the mold showingseparate regulatable means for controlling this expansion.

Fig. 5 is a view similar to Fig. 4, but showing the die expanded. I

This mold consists of two partsa subhead a and a die 6. This die isprovided with a molding cavity 0 and the hot metal is poured therein. Tnthe drawings T have shown only one half of the completed mold as theother half is an exact duplicate and will be abutted up against thishalf and properly located by the dowel pins d. These dies are somachined and finished that they will abut each other and tightly fitagainst each, other to prevent any leakage of the molten metal frombetween the abutting faces of the dies. @bviously the molds can be ofany shape, large or small and we do not limit ourselves to the specificform of mold shown in the drawings.

To counteract the tendency of the die to how when heated during the timewhen the casting is poured, we provide the inclined bearing faces 6 onthe subhead and the hearing laces f on the die which are complementar'yto the bearing faces on the subhead. The die is secured to the subheadat an intermediate point by the screws or bolts 9, and the ends of thedie are secured to the subhead by the screws h but the die is pro-,vided with anelongated slot 2' which permits the ends of the die tofreely slide with respect to the subhead. As the die expands in adirection parallel-to the face of the die due to the change intemperature the inclined bearing face of thedie will ride up theinclined bearing face carried by the subhead, as shown in Fig. 3, andthis will force the free ends of the die toward each other to counteractthe tendency of the die to bow outwardly. This will maintain the face ofthe die in substantially parallel relation with the face or the matingdie and prevent leakage of the molten metal, @bviously this controlmeans could be located to correct warping or bowing from side to side aswell as lengthwise Tu Figs. 4- and 5, we show a modified form ofconstruction in which the expansion plug is" is inserted in the subheadand, rejects through the inclined bearing face, a screw m is backed upagainst'the rear of the expansion plug and by screwing the same in orout the expansion plug may be adjusted. This expansion plug may beformed of any metal that has a greater ratio of expansion than the metalof the mold, such as aluminum, brass, bronze or steel plugs. This plugwhen heated expands at a greater rate than the subhead, and as shown inFig: 5, this bears against this inclined bearing face carried by thedie, and exerts a pressure transs versely of the die at the free ends tocounteract the tendency of the die to bow. With such an expansion plugabetter control of the mold may be had, asthis expansion plug may beadjusted mechanically and by using plugs of different material the samemay expand at a greater or less rate. This gives us an automaticthermostatic control of the mold in addition to the mechanical controlso that the machined faces of the molds remain perfectly parallel. Thelocation and numberv of these expansion plugs depend upon the size andshape of the mold.

Such a control is especially desirable when using molds which have a.much greater dimension in one direction, but such a control can be usedwith molds of any size or shape, and in fact we are using such aconstruction in all of our molds as there is always a slight tendency ofthe molds to bow, no matter what their size and shape is.

This application is directed to the automatic control of mold sectiondistortion in permanent molds, regardless of the direction of bowing ordistortion. It is more particularly directed to the accomplishment ofthis-purpose by means of interposing a mechanical element for furnishinga countervailing effort tending to neutralize these distortions. Thereare claims involved in this case which refer to the use of a thermallyresponsive element in connection with the special mechanical design foraffording the countervailin efi'ort. However, the particular princip eof counteracting the distortion of the mold section by a thermallyresponsive element is not broadly claimed in this application except sofar as it may be covered b the broad claims for the automatic contro ofthe distortion. The utilization broadly of thermally responsive elementsto eifect this control is considered a separate invention and is claimedin application Serial No. 39,053, filed June 23, 1925.

What we claim is:

1. A mold, having in combination a support, a die secured thereto andpermitted to expand and tending to bow when heated, and automatic meansfor applying pressure transversely of the die when the same expands tocounteract the tendency of the die to bow as the result of suchexpansion.

2. A mold, having in combination, a support, adie secured thereto andpermitted to bearin expands to counteract the tendency of the die to bowas the result of such expansion.

3. A mold, having in combination, a support, a die secured thereto at anintermediate point and permitted toexpand and tending to bow whenheated, and automatic means for applying pressure at the ends of the dieand transversely of the die when the same expands to counteract thetendency of the die to bow under such expansion.

4. A mold, having in combination, a support, provided with one or moreinclined bearing faces near the outside edge, and a die secured near thecenter to said support and provided with inclined bearing faces near theends complementary to and engaging the inclined faces on the support,said die permitted to expand and tending to bow when heated, therebycausing the inclined faces on the die to ride up the inclined faces ofthe support, whereby pressure is applied at the ends of the die andtransversely thereof to counteract the tendency expanded.

5. A mold, having in combination a support provided with one or moreinclined bearing faces near the outside edge, adjustable means forcorrectly positioning said bearing face, and a die secured near thecenter to said support and provided with inclined bearing faces near theends complementary to and engaging the adjustable inclined faces on thesupport, said die ermitted to expand and tending to bow w en heated,whereby the inclined faces on the die are caused to ride up the inclinedfaces on the support, to apply a force near the end of the dietransversely thereof to counteract the tendenc of the die to bow whenheated and expan ed.

6. A mold, having in combination, a sup port provided with one or moreinclined faces near the outside edges, thermostatically controlled meansfor positioning the said bearing faces, and a die secured near thecenter to said support and provided with inclined bearing faces near theends complementary to and on aging the inclined faces on the support,said die permitted to expand and tendin to bow when heated, whereby theincline faces on the die are caused to ride up'to the thermostaticallycontrolled inclined faces on the support to counteract the tendency ofthe die to bow when heated and expanded.

7. In a mold, the combination of a die which expands and tends to howwhen heated, and automatic means for controlling the tendency of saiddie to bow.

8. 'In a mold, the combination of a die which expands and tends to bowwhen heatof the die to bow when heated and ed, and means forautomatically applying which when heated-expands in a direction pressuretransversely of said die to counterparallel to the plane of thedie andtends to act the tendency of said die to bow. bow, and means forautomatically applying 9. In a mold, the combination of a die a pressuretransversely of the plane of said '15 5 which is caused to be heated toa higher die to counteract the tendency of said die temperature on oneside than on the other to and thereby expanded unequally thus tend- I 1t st m ny whereof We have afiiXed our ing to how the die,.and automaticmeans g for correcting the tendency of said die to HARRY S. LEE. 10 how.r AMOS E. CHAFFEE.

10. In a mold, the combinationof a die FRED MILLARD.

